The present invention relates to a method for manufacturing a high density connector, and particularly to a double-step insert molding method for manufacturing a high density connector.
As communication technology develops, information transmission between different electronic instruments have become more and more frequent, and simultaneously, the volume of the information transmitted increases and the transmitting frequency has also becomes higher. Furthermore, the trend toward miniaturization decreases the limited inner space of the computer, reducing separation distances between electronic components in the computer. Electrical connectors have had to keep pace with these developmental trends. As a result, high density connectors have, been developed.
High density connectors aim to achieve good communication performance while providing a large quantity of conductive contacts within a limited volume. This is a complex and difficult task, and stricter requirements have been placed on manufactures of such high density connectors.
Pertinent prior art is disclosed in Taiwan Patent Application Nos. 77208350, 79204276, 80213361 and 80209266. As shown in FIG. 7, to manufacture a high density connector, first, a housing 7 is made, usually by plastics injection molding. A pair of shells 8 and a plurality of contacts 6 are formed and stamped out of metal sheets respectively. The contacts 6 are arranged in high density and are commonly connected to a carrier strip 60. The contacts 6 are inserted into corresponding passages 70 defined in the housing 7 before the carrier strip 60 is severed from the contacts 6. The shells 8 are then assembled with the housing 7, thereby completing the connector.
However, the mechanical and electrical performance of the connector may be adversely affected for the following reasons. One, uneven and overthin side walls between adjacent passages lead to a decrease in stability in position of the contacts after they have been positioned within the corresponding passages, as the engaging force between the contacts and the housing is not sufficient to resist mating/withdrawal force of the connector and a complementary connector. Second, both the contacts and the side walls of the passages of the housing may suffer damage due to the mounting of the contacts into the corresponding passages, thereby adversely affecting the electrical communication quality of the connector. Third, the more and more popular surface mounting technology (SMT) needs a coplanarity of soldering portion of contacts in a connector. However, the mechanical difficulties of inserting high density contacts into a housing of a connector increase the difficulty of achieving the coplanarity of the high density contacts, as the soldering portions are likely to be deflected.
Therefore, an improved manufacturing method for high density connectors is desired.
A main object of the present invention is to provide a two-step insert molding method for manufacturing high density connectors which achieves connectors having good communication qualities.
Another object of the present invention is to provide a method for manufacturing high density connectors which has a simplified assembling process yielding a higher production rate.
A method for manufacturing a high density connector in accordance with the present invention comprises five steps. The first step is to prepare essential elements of the connector, such as a dielectric cover, a metallic shell, a pair of guiding members and a plurality of L-shaped contacts, each having a horizontal soldering portion connected to a carrier strip. The second step is to insert mold a pair of dielectric bases around the contacts to get a contact subassembly. The third step is to double insert mold a dielectric housing around the contact subassembly, forming a contact module. The fourth step is to adjust the horizontal soldering portions of the contacts, ensuring a good coplanarity thereof. The fifth step is to assemble the contact module with the cover, the shell and the guiding members, thereby completing the connector. The method of the present invention produces high density contacts having aligned soldering portions with good coplanarity by two-step insert molding to form the contact module. This promotes good electrical communication qualities in the contacts.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.